Lock

ABSTRACT

A lock assembly comprising a locking element having; a body having a first locking axis; at least one tab movable relative to the body, the tab movable between a retracted position and an extended position relative to the first locking axis; a locking surface having at least one retaining element; wherein the lock assembly is operative to adopt a locked condition where the at least one tab engages with a respective one of the at least one retaining element to prevent relative movement between the locking element and the locking surface in at least one direction of the first locking axis.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No. PCT/AU2012/000618, filed Jun. 1, 2012, which claims the priority of Australian Application No. 2011902169, filed Jun. 2, 2011, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present disclosure generally relates to lock assemblies, components for lock assemblies and lock systems which include a lock assembly and/or lock components. The locks of the disclosure have particular application for use in land based excavating equipment to retain a member such as a wear member or rigging to excavating equipment and the disclosure is herein disclosed in that context . However, the locks of the disclosure have broader application, for example for waterborne excavators, such as dredgers, or securing liners to mineral processing equipment and accordingly it is to be appreciated that the disclosure is not limited to that application.

BACKGROUND OF THE INVENTION

Excavating buckets or other digging devices or equipment are typically subject to harsh conditions. Excavating buckets are generally used in various digging and excavation operations. Digging devices typically experience large forces during digging and excavation operations.

Excavation teeth may be provided on the digging edge of the digging devices. Each excavation tooth is formed of a number of parts, commonly a point, an adapter and a lock. The adapter is typically fitted to the digging device and the point fits over the adapter and is retained in place by the lock. In some instances one or more intermediate parts may be also included between the point and the adapter.

The reason that the excavation tooth is formed of a number of parts is to avoid having to discard the entire tooth when only parts of the tooth, in particular the ground engaging part of the tooth (i.e. the point) is worn or broken.

On some digging devices, shrouds are also attached to the digging lip of the device to protect the digging lip edge from wear. Once worn, the shrouds can be removed and discarded and a new replacement shroud attached. This reduces the need to replace the whole device if the lip edge became worn, which would be much more costly than replacing just the shrouds. The shrouds typically comprise a base member that fits around a portion of the lip edge, a wear member that fits over the base member and lock for locking the wear member to the base member and thus to lip, but which also allows the wear member to be removed once worn. The shrouds may be disposed along the entire length of the lip edge or be disposed between excavation teeth that are attached to the lip.

In other digging applications, such as dragline excavating systems, rigging is required to interconnect the dragline buckets to a crane to operate the buckets. Again this rigging which includes various components such as chains, ropes, links and spreader bars, need to be connected together and connected to the dragline bucket. This requires the use of coupling elements such as shackles which include locking arrangements such as locking pins and the like which are retained in place by locks. Again these components are subject to very harsh operational conditions and accordingly the components need to be designed to operate in such harsh conditions.

In heavy engineering applications, such as those discussed above, the components are often subjected to large impact forces. They are also subjected to the ingress of dirt, fines, mud, water and other intrusive materials that can affect mechanical devices. Accordingly, an ongoing problem associated with such equipment is in the operation of the mechanical locks and in particular with their ease of installation, reliability, and ability to unlock after heavy use, wear, and intrusion by foreign materials.

SUMMARY OF THE INVENTION

In some embodiments, there is disclosed a lock assembly comprising: a locking element having; a body having a first locking axis; at least one tab movable relative to the body between a retracted position and an extended position relative to the first locking axis; and a locking surface having at least one retaining element; wherein the lock assembly is operative to adopt a locked condition where the at least one tab engages with a respective one of the at least one retaining element to prevent relative movement between the locking element and the locking surface in at least one direction of the first locking axis.

In some embodiments, a locking element is disclosed having a body having a first locking axis, at least one tab movable relative to the body between a retracted and an extended position relative to the first locking axis. In one form, the tab is arranged to translate relative to the body along a movement axis and that movement axis may be offset from the first locking axis. In another form, it may be radial relative to the first locking axis so that the movement axis intersects the first locking axis. In one form, the tabs may pivot relative to the body between its extended and retracted configurations.

In some embodiments, also disclosed is a component that incorporates a locking surface arranged to receive a locking member of any one of the above forms. The locking surface may be integrally formed with the component or may be formed on a retaining member which is fitted to the component. In some embodiments, the component is part of an excavating machine such as a wear member such as a point or shroud, an adaptor, bucket lip, or part of rigging such as a shackle or link, or part of a retaining system such as a locking pin.

In some embodiments, a locking system is disclosed that comprises a component having a passage; a retaining member receivable in the passage of the component in a locking position; and a lock assembly according to any form disclosed herein disposed in at least part of the passage; wherein in use, the locking element of the lock assembly retains the retaining member in the passage of the housing.

Embodiments of the locking assemblies, elements, and systems have particular application for use in excavating equipment and allow for hammerless installation and removal of the locking elements and good retention performance in the operation of the equipment.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are exploded perspective views of a lock assembly according to the first embodiment.

FIGS. 2A to 2H illustrate a locking and unlocking sequence of the lock assembly according to the first embodiment.

FIG. 2A illustrates the locking ring and locking element before assembly according to the first embodiment.

FIG. 2B illustrates the locking assembly of FIG. 2A, with the locking element inside the cavity of the locking ring, and with the tabs of the locking element disposed in the channels of the locking ring.

FIG. 2C illustrates the locking assembly of FIG. 2B, with the locking element rotated slightly so that the tabs are slightly retracted.

FIG. 2D illustrates the locking assembly of FIG. 2C, with the locking element rotated so that the tabs are retracted and located between the channels and the retaining elements.

FIG. 2E illustrates the locking assembly of FIG. 2D, with the locking assembly in the locked condition, with the tabs extended and engaging with respective retaining elements.

FIG. 2F illustrates the locking assembly of FIG. 2E, with the locking element rotated slightly so the tabs are slightly retracted.

FIG. 2G illustrates the locking assembly of FIG. 2F, with the locking element rotated so that the tabs are retracted and located between the retaining elements and the channels.

FIG. 2H illustrates the locking assembly of FIG. 2G with the locking element rotated so that the tabs are disposed in the channels of the locking ring.

FIG. 3 is a perspective view of a locking element according to the second embodiment with a locking ring.

FIGS. 4A and 4B are exploded top and bottom perspective views of the locking element in FIG. 3.

FIGS. 5A to 5C illustrate sectioned top views of the locking element of FIG. 3 with the tabs in various positions.

FIG. 6 is a perspective view of a locking element according to the third embodiment with a locking ring.

FIGS. 7A and 7B are exploded top and bottom perspective views of the locking element in FIG. 6.

FIGS. 8A to 8B illustrate sectioned top views of the locking element of FIG. 6 with the tabs in various positions.

FIG. 9 is an exploded perspective view of a lock system comprising two lock assemblies and a lock pin.

FIG. 10 is a perspective view of an assembled lock system in FIG. 9.

FIG. 11 is a sectioned side view of the assembled lock system in FIG. 10.

FIG. 12 is an exploded perspective view of a shackle assembly having a locking system.

FIG. 13 is a top view of the shackle assembly of FIG. 12.

FIG. 14 is a side view of the shackle assembly of FIG. 12.

FIG. 15 is a sectioned top view along P-P in FIG. 14.

FIG. 16 is a sectioned side view along R-R in FIG. 13.

FIG. 17 is a schematic exploded perspective view of a shroud assembly having a locking system.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.

This disclosure is directed generally to locks for excavating equipment and large scale mining operations. In some embodiments of such equipment, heavy duty shackles are secured with a shackle pin to connect components, for example, in a dragline. It is important that the shackle is securely locked in position and remains so during a period of robust service and when exposed to harsh conditions including vibration , impact, corrosion and abrasion. After a period of service, components must be replaced, and in a mine location there is a need to make such replacement with minimum downtime of the expensive equipment, and with ease, speed and safety. There is a need to have lock assemblies which can retain the locking pins in position and operate effectively under these harsh conditions.

Disclosed in some embodiments is a lock assembly comprising: a locking element having; a body having a first locking axis; at least one tab movable relative to the body, the tab movable between a retracted position and an extended position relative to the first locking axis; a locking surface having at least one retaining element; wherein the lock assembly is operative to adopt a locked condition where the at least one tab engages with a respective one of the at least one retaining element to prevent relative movement between the locking element and the locking surface in at least one direction of the first locking axis.

In some forms of the lock assembly, the at least one tab is biased towards its extended position when in the locked condition.

In some embodiments, the locking surface is formed on an interior surface defining a cavity, and wherein the locking element is disposed within the cavity when the lock assembly is in the locked condition.

Disclosed in some embodiments, the lock assembly is operative to change from the locked condition to an unlocked condition by a first relative movement between the locking element and the locking surface, the first relative movement causing the at least one tab to move towards its retracted position. At least one of the at least one tab and locking surface may include a camming surface arranged to cause movement of the at least one tab towards its retracted position during the first relative movement.

In some embodiments, the first relative movement includes relative rotation between the locking element and the locking surface about the first locking axis.

In some forms, the lock assembly is operative to adopt the locked condition from an unlocked condition by a second relative movement between the locking element and the locking surface. In some forms, the at least one locking tab is caused to move towards the retracted position during said second relative movement. In at least one form, a camming surface is provided and arranged to cause movement of the at least one tab towards its retracted position during the second relative movement.

In at least some forms, the second relative movement includes relative rotation between the locking element and the locking surface about the first locking axis. In some forms, the second relative movement includes relative translation between the locking element and the locking surface along the first locking axis.

In some forms, the locking surface includes one or more channels that permit location and/or removal of the locking element in the cavity while the at least one tab is in a substantially extended position. In some arrangements, these channels extend generally axially.

In some embodiments, the at least one locking tab is biased towards the extended position. In one form, an elastomeric member is disposed within the lock body and is operative to bias the locking tab into the extended position.

In some embodiments, the locking surface is disposed on a retaining member which in turn, in use is arranged to be fixed to a component, such as a component of excavating equipment. In another form, the locking surface is integrally formed in a surface of the component. For example, the locking surface may define a cavity that forms part of a cast, or otherwise formed, component of the excavating equipment.

In some embodiments, also disclosed is a locking element for a locking assembly in any form disclosed above. Also disclosed is a component which incorporates a locking surface arranged to receive a locking member of the above form. The locking surface may be integrally formed with the component or may be formed on a retaining member which is fitted to the component. In some embodiments, the component is part of an excavating machine such as a wear member such as a point or shroud, an adaptor, bucket lip, or part of the rigging such as a shackle or link, or part of a retaining system such as a locking pin.

Also disclosed in some embodiments is a locking system comprising: a housing having a passage; a retaining member received in the passage of the housing; and a lock assembly according to any form disclosed above, disposed in at least part of the passage; wherein in use, the locking element of the lock assembly retains a retaining member in the passage of the housing.

As illustrated in the figures, some illustrative embodiments of locking assemblies for excavation equipment allow for easy installation and release and reliable operation.

FIGS. 1A and 1B are exploded perspective views of a lock assembly according to a first embodiment.

FIG. 1B illustrates a lock assembly 1 comprising the locking element 3 of FIG. 1A and a retaining member which in the illustrative form is a locking ring 7 of FIG. 1B. The locking ring 7 incorporates a cavity 23 having an interior locking surface 5 and the locking element is received in the cavity and engagable with the locking surface as will be described in more detail below.

In the illustrative form, the locking element 3 has a body 4 which is generally cylindrical having an axis CL which forms a first locking axis of the body 4 and about which the locking element is arranged to rotate in use. The locking element 3, as illustrated, also has three tabs 9 movable between an extended position and a retracted position relative to the first locking axis. The locking surface 5 has three retaining elements 11, which when engaged with the respective tabs 9, prevent relative movement between the locking element 3 and the locking surface 5 in at least one direction of the first locking axis. While the illustrative form shows three tabs, it will be appreciated that the locking assembly may include more or fewer tabs depending on requirements and space constraints.

The locking element 3, as illustrated, will now be described in detail. The locking element 3 is comprised of a flat cylindrical, “puck” like body 4, advantageously made of metal. The top surface 13 is provided with a drive portion in the form socket 15 for engagement with a wrench or other drive tool. Although the illustrated socket is of a substantially square shape, it is to be appreciated that other socket shapes or configurations of drive portions (such as spigots) may be used. A bottom surface 14 of the element 3 provides a bearing surface for the element and retains other components of the locking element 3.

Along the peripheral side 17 of the body 4, the tabs 9, which typically are also made of metal, are biased to project in an extended position as generally shown in FIG. 1A. The tabs 9 are movable to a retracted position, wherein the tabs 9 are displaced inwardly towards or into the peripheral side 17. In the locking element 3 of FIG. 1A, the tabs 9 translate between the extended position and the retracted position along a movement axis that is generally perpendicular to the first locking axis, but chordal (i.e. it does not intersect the movement axis but rather forms a chord to the cylindrical body). The direction of the movement axis disposed in this chordal arrangement may advantageously be geometrically related with the camming surfaces as described later.

The tabs 9 are provided with a first cammed surface 19. The first cammed surface 19 is provided such that when the locking element 3 is rotated clockwise (as seen looking down at top surface 13), the first cammed surface 19 will be the leading surface of the tabs 9. The first cammed surface 19, on rotation of the locking element 3 in the clockwise direction, advantageously cooperates with the locking surface 5, to move the tab 9 towards the retracted position. This will be described later.

The locking element 3 includes one or more biasing members within the body which are arranged to bias the tabs into their extended position. In the illustrative form, the biasing members are in the form of an elastomeric block 21 which is secured behind the back surface tabs 9. Compression of the elastomeric block allows the tabs to move towards their retracted position while imparting a biasing force on to the tabs to return to their extended position as the block tends to move back to its natural uncompressed state. An advantage of this arrangement is that the surface interface between the tabs and the block is effectively sealed thereby reducing the susceptibility of fines building up in the locking element that would prevent movement of the tabs to their retracted position. However, it is to be appreciated that other forms of biasing may be used, including leaf or helical springs.

The locking surface 5 in FIG. 1B will now be described in detail. In the illustrated embodiment showing FIG. 1 B, the locking surface 5 is provided within a cylindrical cavity 23 of the locking ring 7. It is to be appreciated the locking surface 5 is not limited to being disposed on a locking ring 7, and may be disposed inside other shaped members. An opening 24 is provided at the base of the cavity 23 to provide passage for other members to bear against the bottom surface 14 of the locking element 3, when the locking assembly is in the locked condition.

The cylindrical cavity 23 is sized to snugly fit the cylindrical body 4 of the locking element 3 to reduce the build up of dirt, fines and other loose material in the locking assembly 1. The locking surface 5 is provided with three evenly spaced recesses 25, to match the respective tabs 9 of the locking element 3. Advantageously, the geometry of the tabs 9 matching the recesses 25 would reduce space for the build up of foreign matter.

The retaining element 11 forms at least one wall of the recess 25, which when engaged with tabs 9, prevent relative movement of the locking element and the locking surface along the first axis. In the illustrative form, these retaining elements are the upper under surfaces defining the recesses 25 which are in facing relation with the tabs when located in those recesses.

Each recess 25 also includes a second cammed surface 27. When the locking element 3 is rotated clockwise relative to the locking surface, the second cammed surface 27 cooperates with the first cammed surface 19 to move the tabs 9 towards the retracted position. It is to be appreciated however, that such a camming action does not require both the first and second cammed surface, and that one cammed surface on one component may cooperate with a respective opposing portion to facilitate camming action for movement of the tabs 9.

The locking surface 5 is also provided with three channels 29 extending longitudinally along the cavity 23. The channels 29 permit the location of the locking element 3 into the cavity 23 while the tabs 9 are in an extended position. This allows easy insertion of the locking element 3 into the cavity 23, without tabs 9 interfering or providing undue friction. The channels 29 extend down the cavity 23 sufficiently to allow uninhibited insertion of the locking element 3 into the cavity along the first locking axis to a position, such that the tabs 9 are axially aligned to the recesses 25. From this position, the tabs 9 can enter the recesses 25 and engage the locking elements by relative rotation of the locking element 3 and the locking surface 5 without further relative movement along the first locking axis.

The channels 29 are also provided with a third cammed surface 31. This surface facilitates movement of the tabs 9 towards a retracted position in the same manner as the second cammed surface 27.

The locking and unlocking sequence of the lock assembly according to the first embodiment will now be described with reference to FIGS. 2A to 2H.

FIG. 2A illustrates the locking ring 7 having a locking surface 5 before assembly with the locking element 3. To assemble lock assembly 1, the tabs 9 of the locking element 3 are aligned with respective channels 29, and the cylindrical body 4 inserted into the cavity 23 of the locking ring 7.

As illustrated in FIG. 2B, the channels 29 provide clearance for the tabs 9 while the locking element 3 is being inserted. The locking element 3 is positioned into the cavity 23 to a position such that the tabs 9 and the recesses 25 are on the same perpendicular plane to the first locking axis with the tabs 9 in the channels 29, and the recesses 25 angularly displaced from the channels 29 in the cylindrical cavity 23.

For ease of reference, the relative rotation of the locking element 3 with the locking surface 5 is described in terms of clockwise rotation around the first locking axis when seen from a top view (as illustrated). As a reference, the angular position of the locking element 3 relative to the locking surface as shown in FIG. 2B is assigned a zero position. The relative angular displacement described is for ease of reference for this described embodiment, and it will be appreciated that other embodiments will not be limited to specific angular displacements described below.

To lock the locking assembly from the position shown in FIG. 2B, the locking element 3 of the illustrative form is rotated such that the tabs 9 engage the retaining elements 11. To achieve this, a wrench, or other suitable drive tool is engaged with the socket 15 to drive the locking element 3 clockwise.

FIG. 2C illustrates that as the body 3 rotates from its zero position, the first cammed surface 19 of the tab cooperates with the third cammed surface 31 of the channels 29 to provide a camming action to move the tabs 9 towards the retracted position.

This camming action moves the tabs into a position as illustrated in FIG. 2D where the tabs are retracted substantially fully to be at least almost flush with the lock element body. In FIG. 2D, the locking element 3 and the locking surface are angularly displaced by approximately 30 degrees clockwise, with the tabs 9 retracted and angularly located between the channels 29 and the recesses 25.

The locking element 3 is further rotated until the tabs 9 are angularly located with the recesses 25, whereby the tabs 9 are free to move under the biasing force of the elastomeric block towards the extended position and engage with the retaining elements 11. This is the locked condition and is best illustrated in FIG. 2E where the locking element 3 and locking surface 5 are displaced by 60 degrees. The tabs 9 engage with the retaining elements 11 to prevent the locking element 3 from moving relative to the locking surface 5 along the first locking axis. In this locked condition, the tabs 9 substantially occupy the recesses 25, thereby reducing void space where foreign material may build up.

To unlock the locking element 3 from the locking surface, the locking element 3 is further rotated relative to the locking surface 5. This movement is shown in FIGS. 2F-2H.

As the body 3 is rotated, the first cammed surface 19 of the tab cooperates with the second cammed surface 27 of the recess 25 to provide a camming action to move tabs 9 towards the retracted position. FIG. 2F illustrates the locking element 3 displaced by 75 degrees from the locking surface 5, whereby the tabs 9 a slightly moved towards the retracted position.

Throughout the movement of the tabs 9 between the extended and retracted positions, their respective movement axes are chordal to the axis of rotation of the locking element 3. This is advantageous as the movement axes are substantially coaxial to a normal axis of the first and/or second cammed surfaces. This reduces friction and off axis forces between the tabs 9 and the body 4 of the locking element, thereby preventing binding and wear.

Further rotation causes the tabs 9 to further retract as illustrated in FIG. 2G, whereby the locking element 3 is displaced by 90 degrees, and the tabs 9 are angularly displaced between the recesses 25 and the channels 29. It is possible in this unlocked condition to extract the body 4 of the locking element from the cavity 23. This may be achieved by pulling, pushing or levering the body from the locking surface 4.

Alternatively the body 4 of the locking element 3 can be rotated further, as illustrated in FIG. 2H where the locking element 3 is displaced by 120 degrees from the locking surface 5. The locking element 3 is positioned so that the tabs 9 are now positioned within the channels 29. Advantageously, the tabs 9 have clearance to move towards the extended position, as well as being provided uninhibited movement along the channels 29. This allows for easier removal of the locking element 3 from the cavity 23 as there is reduced friction between the tabs 9 and the cavity 23.

Advantageously, the lock assembly 1 does not require the application of axial forces or bias along the first locking axis when locking or unlocking the lock assembly. In known prior art locks, it was necessary to apply axial force and/or axially move the locking element when locking or unlocking. A consequence of this is the requirement to provide a void or clearance to allow for axial movement, thereby providing a space for foreign material to collect and jam the locking assembly. By providing a lock assembly 1 with self occupying components, and with minimal voids, it reduces the chance of foreign material intruding and jamming the assembly.

A second embodiment of the locking element will now be described with reference to FIGS. 3 to 5C. The locking element 103 has tabs 109, that has a movement axis extending radially from the first locking axis of the body 104 of the locking element 103. FIGS. 5A to 5C illustrate various positions of the tabs 109 as they move radially between their extended and retracted positions.

A third embodiment of the locking element will now be described with reference to FIGS. 6 to 8C. The locking element 203 has tabs 209, that are pivotally attached by pivots 210 to the body 204. The pivots 210 allow the tabs to swing outwardly between an extended position and a retracted position. A resilient element 221 is provided for each tab 209 to bias the tabs to the extended position. FIGS. 8A to 8C illustrate various positions of the tabs 209 from an extended position to a retracted position.

A further embodiment of the locking element (not shown) may have tabs with additional camming surfaces on the tabs. In one form, the additional camming surfaces may allow the lock assembly to be locked and unlocked in both directions (i.e. clockwise and anti-clockwise when viewed from the top view). A further alternative is to have camming surfaces on the underside of the tabs (i.e. the face when viewing towards the bottom surface 14 of the body), thereby allowing the lock element 3 to be push fit into the cavity 23 of the lock ring 7. This allows locking of the lock element 3 to the lock surface 5 without relative rotation of the lock element 3 and the lock surface 5. To unlock, the lock element 3 may be rotated to move the tabs towards the retracted position as described in the above embodiments.

A lock system will now be described with reference to FIGS. 9 to 11. Referring to FIG. 9, the lock system 302 comprises two lock assemblies 1 as previously described, and a retaining member in the form of a lock pin 306. The lock pin 308 has opposing end surfaces 308 for abutment with the bottom surface 14 of the locking element 3, thereby retaining the lock pin 308 in position when the lock assembly is in a locked condition.

FIGS. 10 and 11 illustrate the lock system 302 assembled, with the lock assemblies 1 in a locked condition to retain the lock pin 306. As best illustrated in FIG. 11, the system 302 is oriented such that end surfaces 308 are in abutment with bottom surface 14, thereby preventing the lock pin 306 from axial movement without imparting movement of one or the other of the locking element along their respective first locking axis. Further when in the locked condition as shown, the end surface 308 and bottom surface 14 are in contact without providing any significant void or space for foreign material to collect. Also rotation of the locking element 3 during locking and unlocking, the end surface 308 and bottom surface 14 maintain this contact without producing voids. This reduces the chance of foreign material to jam the lock assembly and lock system.

An application of the lock assembly 1 and lock system 302 to a shackle assembly 412 will now be described with reference to FIGS. 12 to 16. FIG. 12 illustrates an exploded view of a shackle assembly 412, comprising a shackle 414, a pin 416, and a lock system 302 described above.

The shackle 414, has pin apertures 418 for receiving the pin 416, and two lock assembly apertures 420 for receiving respective lock assemblies 1. A first lock pin groove 422 is provided between the two lock assembly apertures 420.

The pin 416 has a second lock pin groove 424 transverse to the main axis of the pin 416. When the shackle assembly 412 is assembled, as shown in FIGS. 13 to 16, the pin 416 is located to pass through the pin apertures 418. The first lock pin groove 422 of the shackle 414 and the second lock pin groove 424 of the pin 416 are aligned to form a passage for the lock pin 306 to pass through, as best illustrated in FIG. 15. The lock pin 306 prevents the pin 416 from moving out of the pin apertures 418, thereby retaining the pin 416 relative to the shackle 414.

The lock pin 306, in turn is retained in the passageway formed by grooves 422 and 424, by the lock assemblies 1 disposed at the lock assembly apertures 420. The locking ring 7 is fixed to the lock assembly apertures 420, by welding, press fit, adhesives or any other suitable method of fixing. The lock pin 306, once in place in the passageway formed by the grooves 422 and 424 is then retained in the passageway by locking the lock elements 3 with respective locking surfaces 5. This is best illustrated in FIG. 16. As illustrated, the bottom surfaces 14 of the locking elements 3 abut the end surfaces 308 of the lock pin 306, thereby preventing axial movement of the lock pin 306 along the first lock axis.

To remove the pin 416 from the shackle 414, either one, or both of the lock elements 3 are unlocked and removed from the respective lock assemblies 1. The lock pin 306 is then removed through either one of the two lock assembly aperture 420. The pin 416 may then be removed from pin apertures 418.

Although the locking ring 7 has been described as a separate element fixed to the shackle, it is to be appreciated that other alternatives for providing a locking surface 5 are possible. For example, the locking surface 5 may be machined, cast, forged or hammered directly onto the surfaces of the two lock assembly apertures.

Furthermore, although the above application has been described in relation to retaining a lock pin for a pin of a shackle assembly, the lock assembly 1 may have broader application. For example, the lock assembly 1 may be used to retain the pin. The lock assembly may be used as part of a retention mechanism for a shroud, tooth, adaptors including, but not limited to ground engagement tools, and drag line buckets.

A further such application of the lock assembly 1 used in a lock system 500 for connecting a shroud 502 to a bucket lip 504 is shown in FIG. 17. Similar to the earlier embodiment, the lock assembly 1 (comprising the rotatable locking element 3 and locking surface) is arranged to retain a retaining member (in the form of locking staple 506) in locked position within passage 508 that is formed by aligned through holes formed in the shroud 502 and lip 504. Insertion of the staple into passage 508 prevents the release of the shroud from the lip. The lock assembly is arranged to locate over the bridge 510 of the staple and is disposed within a recess of the passage. The locking surface 5 is formed on a ring fixed to the shroud 502 (but could be otherwise made integral with the shroud) and locking of the locking element 3 to the locking surface 5 prevents release of the staple from components.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims. 

1. A lock assembly comprising: a locking element having; a body having a first locking axis; at least one tab movable relative to the body, the tab movable between a retracted position and an extended position relative to the first locking axis; a locking surface having at least one retaining element; wherein the lock assembly is operative to adopt a locked condition where the at least one tab engages with a respective one of the at least one retaining element to prevent relative movement between the locking element and the locking surface in at least one direction of the first locking axis; and wherein the lock assembly is operative to change from the locked condition to an unlocked condition by a first relative movement between the locking element and the locking surface, said first relative movement causing said at least one tab to move towards its retracted position.
 2. The lock assembly according to claim 1, wherein in the locked condition, the at least one tab is biased towards its extended position.
 3. The lock assembly according to claim 1, wherein the locking surface is formed on an interior surface defining a cavity, and wherein the locking element is disposed within the cavity when the lock assembly is in the locked condition.
 4. The lock assembly according to claim 3, wherein at least one of the at least one tab and locking surface includes a camming surface arranged to cause movement of the at least one tab towards its retracted position during said first relative movement.
 5. The lock assembly according to claim 3, wherein the first relative movement includes relative rotation between the locking element and the locking surface about the first locking axis.
 6. The lock assembly according to claim 1, wherein the lock assembly is operative to adopt the locked condition from an unlocked condition by a second relative movement between the locking element and the locking surface.
 7. The lock assembly according to claim 6, wherein the at least one locking tab is caused to move towards the retracted position during said second relative movement.
 8. The lock assembly according to claim 7, wherein at least one of the at least one tab and locking surface includes a camming surface arranged to cause movement of the at least one tab towards its retracted position during said second relative movement.
 9. The lock assembly according to claim 7, wherein the wherein the second relative movement includes relative rotation between the locking element and the locking surface about the first locking axis.
 10. The lock assembly according to claim 7, wherein the second relative movement includes relative translation between the locking element and the locking surface along the first locking axis.
 11. The lock assembly according to claim 2, wherein the locking surface includes one or more channels that permit location and/or removal of the locking element in the cavity whilst the at least one tab is in a substantially extended position.
 12. The lock assembly according to claim 1, wherein the at least one tab is arranged to move relative to the lock element body along a movement axis between the extended and retracted positions, the movement axis being generally perpendicular to the first axis and offset from the first axis.
 13. The lock assembly according to claim 2, further comprising at least one biasing member engagable with the at least one tab to bias the or each tab into the extended position, wherein the at least one biasing member is one or more elastomeric members which are engagable with a rear surface of the respective tabs and which are arranged to compress on movement of the at least one tab from its extended position towards its retracted position.
 14. The lock assembly according to claim 1, wherein the locking surface is formed on a retaining member.
 15. A locking system comprising: a housing having a passage; a retaining member received in the passage of the housing; and at least one lock assembly comprising a locking element having; a body having a first locking axis; at least one tab movable relative to the body, the tab movable between a retracted position and an extended position relative to the first locking axis; a locking surface having at least one retaining element; wherein the lock assembly is operative to adopt a locked condition where the at least one tab engages with a respective one of the at least one retaining element to prevent relative movement between the locking element and the locking surface in at least one direction of the first locking axis; and herein the lock assembly is operative to change from the locked condition to an unlocked condition by a first relative movement between the locking element and the locking surface, said first relative movement causing said at least one tab to move towards its retracted position, the lock assembly being disposed in at least part of the passage; wherein in use, the locking element of the lock assembly retains the retaining member in the passage of the housing.
 16. The locking system according to claim 15, wherein the retaining member retains a component wherein the component is any one of a shroud, tooth, adaptor or coupling for a ground engaging tool. 